1821.] Scientific Intelligence. 395 



Article IX. 



SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS 

 CONNECTED WITH SCIENCE. 



I. Education of Mechanics. 



A school for the education of mechanics has been established at 

 Edinburgh, and upwards of 200 students have already enrolled them- 

 selves for improvement in their several trades. 



The establishment of free drawing schools has long been a desidera- 

 tum and is no less essential in the more humble branches of mechanic 

 industry than in the higher walks of our manufactures. Somewhat 

 similar to this was attempted in France during the Buonapartean 

 regime, and its success was very fully evinced by the great improve- 

 ment displayed in their bronze and ormolu ornaments, as well as in 

 their china manufacture, which for a time superseded those of our own 

 country. From this it will be seen, that although we are not anxious 

 to increase the already too numerous class of artists, who seldom pass 

 beyond the bounds of mediocrity, we are yet persuaded that the tailor, 

 or carpenter, would derive material benefit from employing his leisure 

 hours in a school dedicated to those parts of design which are essential 

 towards sketching with correctness the anatomy of the human figure, 

 or the fitting up of a building. 



II. Application of the Air-Pump. 

 Till within the last 10 years, the use of the air-pump had been exclu- 

 sively confined to the service of the pneumatic chemist and philoso- 

 phical experimentalist. Now, however, this valuable instrument is 

 very generally employed in many of our manufactures. We believe 

 that the sugar refiners working under Messrs. Howard and Hodgson s 

 patent were the first who employed it in a large way. It is a fact 

 very generally known that fluids boil at a lower temperature be- 

 neath the exhausted receiver of an air-pump than when exposed to 

 the ordinary pressure of the atmosphere, and the sugar refiner, tak- 

 ing advantage of this principle, very readily prevents the charring 

 incident to the old process. To accomplish this, it is merely necessary 

 to enclose the pan containing the saccharine fluid in a close vessel, and 

 by the continued action of an air-pump, the air is so far ranfied as to 

 produce ebullition at a temperature seldom exceeding 100 of Fahren- 

 heit's thermometer. , . . • • i 



This simple instrument has also been employed in the sizing and wet- 

 ting of paper. In the former case, the paper is piled up evenly in a 

 vessel capable of being rendered air-tight, and a vacuum being first 

 formed, the size is introduced, which is afterwards pressed in by the 

 force of the atmosphere; passing through the pores of the paper with- 

 out injury to its fabric. In the process of dyeing, also, the air-pump 

 has been found highly efficacious. In the ordinary way, the cloth is 

 merely immersed in the dye, so that the internal part is of a lighter 

 hue ; but, in this case, the colouring matter passes through the entire 

 fabric. 



